Magnetic resonance imaging is an imaging method in which nuclear spins inside an object placed in a static magnetic field are magnetically excited by RF signals having the Larmor frequency, and an image is reconstructed from MR signals generated upon the excitation.
One of the high-speed imaging methods in the field of magnetic resonance imaging is BPI (Echo Planar Imaging). EPI is designed to perform imaging while reversing a gradient magnetic field at high speed, and hence acquired echo data includes a phase error. Therefore, distortion occurs in an image reconstructed based on such echo data.